EFFECTS OF INANITION IN THE PREGNANT ALBINO RAT. 123 



birth and continued to 8 months or a year (Jackson, 1915a; Stewart, 1918), the 

 kidneys showed a slight loss in weight. 



In both acute and chronic inanition in adult rats the kidneys lose in weight 

 relatively slightly less than the body as a whole (Jackson, 1915). 



Testes and epididymides. — The Wistar norm (Donaldson, 1915) for the weight 

 of the testes in the newborn rat is 0.004 gram or 0.081 per cent of the body-weight, 

 4.9 grams. Stewart (1918a) gives the weight of the testes in the newborn as 0.0027 

 gram, or 0.053 per cent of the body-weight, 5.08 grams. In my normal newborn 

 the average weight of the testes is 0.0029 gram, or 0.0G0 per cent of the body-weight, 

 4.92 grams. There are no prenatal control males in Group I, consequently no 

 testes for comparison. 



In my prenatal controls the weight of the testes forms 0.050, 0.047, 0.042, and 

 0.040 per cent of the body in groups II to V, respectively (computed from table 5). 

 Thus the relative weight of the testes in the prenatal controls is considerably less 

 than that in the newborn rat. It is to be noted that the relative weight is higher in 

 the smaller rats and decreases as the birth-weight is approached. That is, the 

 testes are lagging behind the body-growth as a whole. In order to reach the relative 

 weight normal for the testes at birth, there must necessarily be a period of very 

 active growth in the testes just before birth (in fetuses between the body- weights of 

 4.1 and 5 grams). 



In my test rats the average weight of the testes forms 0.030, 0.052, 0.056, 0.048, 

 and 0.050 per cent of the body-weight in Groups I to V, respectively (computed from 

 table 5) . Thus the relative weight of the testes is slightly higher in the test rats than 

 in the prenatal controls. In both, however, the relative weight of the testes is 

 markedly below that in the normal newborn rat. 



The absolute weight of the testes in the test rats averages 16 per cent above the 

 prenatal controls (in 4 groups). 



In postnatal starvation, the testes during the first weeks of life manifest a re- 

 markable growth tendency. Stewart (1918a) found that the absolute weight of the 

 testes in rats kept at a constant birth-weight for 16 days exceeded that of newborn 

 controls by 374 per cent (table 6), which was the strongest growth tendency ex- 

 hibited by any organ in the body. In rats underfed from birth to 3 weeks, the in- 

 crease in the absolute weight of the testes above that of controls of the same body- 

 weight (10 grams) is less, being 188 per cent (Stewart, 1918). In a longer period 

 of underfeeding (birth to 10 weeks), the testes show a gain in weight of but 51 per 

 cent (Stewart, 1918) ; while in underfeeding from 3 weeks of age to 10 weeks the 

 testes gain 34 per cent (Jackson, 1915a). With prolonged starvation, however, the 

 testes may lose considerably (Stewart, 1918), or may show practically no change 

 (Jackson, 1915a). 



In both acute and chronic inanition, in adult rats, the testes lose at about the 

 same relative rate as the body as a whole, the loss being slightly more marked in 

 chronic inanition (Jackson, 1915). 



